Lid latch and interlock mechanism for clothes washing machines

ABSTRACT

An automatic clothes washing machine including means locking the washing machine lid closed during a spin water extraction cycle. Closure of the washing machine lid pivots a latch into engagement with a keeper secured to the lid, the pivotal movement of the latch moving a slide closing a first switch. Closure of the switch energizes a solenoid actuating a locking arm into engagement with the slide, locking the slide in a lid latched position while also closing a second switch. The second switch is in the spin water extraction circuit and conditions the circuit for operation when that portion of the clothes washing cycle is demanded by an automatic control timer. Means are associated with the first switch opening it when the spin tub is out of balance.

United States Patent [191 [111 3,763,670 Harrold [45] Oct. 9, 1973 LID LATCH AND INTERLOCK 3,504,777 4 1970 Waugh 192/136 MECHANISM FOR CLOTHES WASHING MACHINES Inventor: Marshall C. Harrold, Dayton, Ohio General Motors Corporation, Detroit, Mich.

Filed: Mar. 2, 1972 Appl. No.: 231,234

Assignee:

References Cited UNITED STATES PATENTS Beck 68/12 R x Primary Examiner-John Petrakes Assistant Examiner-Philip R. Coe Attorney-Frank J. Soucek et al.

[5 7] ABSTRACT An automatic clothes washing machine including means locking the washing machine lid closed during a spin water extraction cycle. Closure of the washing machine lid pivots a latch into engagement with a keeper secured to the lid, the pivotal movement of the latch moving a slide closing a first switch. Closure of the switch energizes a solenoid actuating a locking arm into engagement with the slide, locking the slide in a lid latched position while also closing a second switch. The second switch is in the spin water extraction circuit and conditions the circuit for operation when that portion of the clothes washing cycle is demanded by an automatic control timer. Means are associated with the first switch opening it when the spin tub is out of balance.

4 Claims, 7 Drawing Figures PATENTEU 91975 I 3 763 670 SHEEI 1 BF 3 1 LID LATCH AND INTERLOCK MECHANISM FOR CLOTHES WASHING MACHINES The present invention relates to a clothes washing machine cabinet lid latch and interlock mechanism and more particularly to such a mechanism also sensing spin tub out of balance and being operable to shut the machine down when such conditions occur.

Previously, in the washing machine art, separate lid interlocks operable to shut the machine down during the spin water extraction cycle when the cabinet lid is opened have been used. Other devices have included latches used to hold the lid closed while the spin tub is operating. Also tub out of balance sensing mechanisms shutting the machine down during severe clothes load out of balance conditions have been used.

In accordance with the present invention, an improved lid latch and interlock mechanism is provided in which the features of latching the lid closed while the tub is spinnning and sensing tub out of balance both are incorporated into a single mechanism. The lid latch and interlock device of my invention is mounted adjacent the access opening in a washing machine cabinet that is selectively opened and closed by a lid pivotally mounted on the cabinet. A keeper is mounted in the lid and extends within the access opening when the lid is closed, engaging an anvil portion of a latch assembly in the form of a bell crank. Engagement of the keeper with the anvil rotates the latch into a position interfering with opening movement of the keeper. Rotation of the latch extends a spring biased slide assembly actuating a first switch in the washer control circuitry which in turn energizes a solenoid retracting a spring biased armature rotating a locking arm. The slide assembly includes a primary slide slidably supporting a secondary slide. The locking arm engages a notch in the primary slide retaining it in an extended position. Rotation of the locking arm closes a second switch conditioning the washer control circuitry for the spin water extraction cycle when demanded by the automatic timer advancing the complete washing cycle. The lid latch and interlock assembly further includes a bump arm responsive to spin tub out of balance. When the clothes are not evenly distributed in the tub, it gyrates, while being rotated, and moves into contact with the bump arm whereupon sufficient movement of the tub out of a circular path pivots the bump arm moving the slide assembly actuating the aforementioned first switch open and the spinning cycle is shut down. The solenoid is deenergized and the locking arm moves to its spring biased position out of the slide notch. The second switch is opened as the locking arm disengages the slide notch. When the lid is opened for repositioning the clothes, the slide assembly then returns to its spring biased retracted position.

A significant feature of the invention resides in utilization of a short stroke solenoid. The solenoid preferred, but not necessary to operation of the subject invention, is one having a stroke of approximately 0.080 inches thereby permitting use of a small unit providing a maximum operational force while minimizing coil current should the armature be forcibly prevented from seating. A further advantageous feature of the present invention is that by virtue of the arrangement and manner of association of the, elements, the possibility of applying a force in direct opposition to the solenoid and causing damage thereto is entirely prevented. The slide assembly and the locking arm are arranged to prevent the occurrence of such damage thereby providing longer useful life of the solenoid than would occur if the slide could apply such an oppositional force.

Accordingly, a general object of the present invention is the provision of a lid latch and interlock mechanism also including shut down means responsive to spin tub out of balance.

A further object of the present invention is to provide a mechanism including a bell crank latch engaged by a keeper attached to a washing machine lid, such engagement rotating the latch into a position of interference with keeper movement of the lid open and simultaneously extending a slide assembly closing switches energizing a solenoid locking the slide extended and conditioning the washing machine control circuitry for a spin cycle.

Another object of the present invention is to provide a washing machine lid latch and interlock mechanism including a bell crank latch having an anvil portion engaged by a keeper on closure of the lid rotating the latch into a position preventing keeper movement open, rotation of the bell crank latch extending a normally spring biased retracted slide assembly, the slide closing a first switch energizing a solenoid rotating a locking arm into a latching position retaining the slide extended, rotation of the locking arm closing a second switch conditioning the washing machine control circuitry for a spin water extraction cycle.

A still further object of the present invention is to provide a washing machine lid latch, interlock and spin out of balance shut down mechanism attached as a single unit to the washing machine cabinet adjacent an access opening closed by a lid, the mechanism including a short stroke solenoid energized by rotation of the latch into a position blocking movement of a lid attached keeper toward a lid open position, the solenoid retracting an armature thereby locking the lid latched, and the short stroke of the solenoid minimizing current flow in the winding thereof should the movement of the armature be prevented from freely moving within the coil.

It is yet another object of the present invention to provide a lid latch, interlock and spin tub out of balance shut down mechanism particularly suitable for clothes washing machine application having features of construction, combination and arrangement making it simple, readily manufactured, reliable, inexpensive and otherwise commercially useful.

The novel features which I believe to be characteristic of the present invention are set forth with particularity in the appended claims. My invention itself, however, both as to its structure and mode of operation, together with further objects and advantages thereof, will best be understood by reference to the following description taken in conjunction with the accompanying drawings, in which:

FIG. 1 is a view in perspective of an upper portion of a washing machine cabinet showing the lid latch, interlock and spin out of balance mechanism of the subject invention mounted adjacent the cabinet access opening.

FIG. 2 is a view in cross-section through axis 2-2 of FIG. 1 with the cabinet lid closed and the lid attached keeper in engagement with the lid latch, interlock and spin out of balance mechanism wherein the latch is rotated to a keeper blocking position preventing opening of the lid.

FIG. 3 is a view in cross-section, like that of FIG. 2, showing the cabinet lid partially opened; the keeper moved out of engagement with the lid latch, interlock and spin out of balance mechanism and the latch rotated out of the path of the keeper.

FIG. 4 is a top plan view on axis 4-4 of FIG. 3 of the mechanism with the latch cover removed and a portion of the switch and interlock cover broken away.

FIG. 5 is a schematic diagram of the washing machine automatic control circuitry including the switches of the lid latch, interlock and spin out of balance mechanism and the locking solenoid.

FIG. 6 is a bottom plan view further showing the organization of the elements of the subject mechanism.

FIG. 7 is an exploded perspective view illustrating operational organization of the latch, anvil carriage, slide assembly and the out of balance switch actuating arm of the subject invention.

Referring to FIG. 1, a washing machine cabinet 10 containing an access opening 12 for depositing clothes into a washing and spin tub arrangement, not shown, has a lid 14 pivotally mounted adjacent the opening. The lid latch, interlock and spin out of balance shut down mechanism 16 of the subject invention is mounted adjacent opening 12 on the underneath surface of a top panel 18 containing the opening. A keeper 20 is secured to the lid 14 in a position to engage parts of the lid latch and interlock mechanism when the lid is closed.

In FIG. 2, the lid 14 is shown closed with the keeper 20 attached to a bent back portion 22 of the lid by a threaded machine screw 24 engaging a fastening block 26 secured to the lid. As can be readily seen, the keeper 20 contains a slot 28 receiving the bent back portion 22 of the lid and includes an integral depending striking portion 30 engaging components of the lid latch and interlock mechanism. The lid latch and interlock mechanism 16 of the present invention includes a base 32 that is secured to the cabinet top panel in any conventional manner. The base 32 contains a substantially rectangular aperture 34 near its left end as viewed in FIG. 2. A bifurcated latch bell crank 36 is pivotally mounted in the aperture 34 on a pin 38 while a latch cover 40 encloses the latch bell crank and is secured to base 32 by screws 42 which also retain a bottom plate 43. The latch cover 40 contains opposed vertical slots 44 opening inwardly of the cover, each receiving a side portion 46 of an anvil carriage 48 best shown in FIG. 7. Likewise the base 32 contains slots 50 in alignment with the cover slots 44, each also receiving the side portions 46 of the carriage 48 permitting vertical movement thereof within the base aperture 34. The oppositely disposed anvil carriage side portions 46 and the base slots 50 are best shown in FIG. 4. The bifurcated latch bell crank 36 is also best shown in FIG. 4 as including lower spaced arms 52 extending under laterally projecting shoulders 54 of the anvil carriage 48. A pin 56 extends across the space between the arms 52 and has its ends secured respectively thereto. The latch bell crank 36 further includes an integral axially extending latch 58, the top surface of which is shown. With reference to FIG. 6, the bifurcated latch bell crank 36 is pivotally mounted in base 32 on a pin 38 received in slots 59. The pin 38 is retained in the slots 59 by the plate 43 that is secured to the base by screws 42.

A primary slide 60, best shown in detail in FIG. 7 and in assembly in FIGS. 2, 3 and 4, terminates in an end portion 62 containing a lateral slot 64 receiving the pin 56 attached to the arms 52 of carriage 48 as previously described. The base 32 is formed with a somewhat centrally disposed longitudinal recess 66 of rectangular cross-section slidably receiving the slide 60 for movement between retracted and extended positions. The slide 60 includes an integral laterally projecting tab 68 engaged by one end of a coil spring 70, the other end of the spring engaging an abutment 72 formed on the base 32 which includes a top surface slidably supporting a portion of the slide 60. The spring biases the slide 60 to the normally retracted position of FIG. 3. Slide 60, in a manner similar to that of base 32, includes a longitudinal slot 74 receiving a smaller secondary slide 76. The secondary slide 76 includes an upstanding tab 78 which engages a switch actuating arm 79. The secondary slide 76 has laterally extending tabs 80 and 82 received within a widened recess 84 in the primary slide 60, the tabs 80 and 82 engaging abutments 86 and 88 preventing movement of the secondary slide toward the latch 58 as best shown in FIG. 4.

The base 32 also receives a switch cover 90 which is retained thereon by a plurality of self-threading screws 92. The switch cover has a first microswitch 94 secured to its underneath surface 96, the switch 94 having the switch actuating arm 79 secured thereto. A second switch is also attached to the underneath surface 96 of the cover 90 and is positioned to place switch actuating button 101 in a preselected position.

The base 32 further includes an axially extending vertical flange 102 receiving a solenoid assembly 104 mounted in a bracket 106, the bracket being secured thereto by means of bolts 108 threadably received in the bracket 106. The solenoid assembly 104 includes an armature 110 biased to an extended position by a spring 112 and pivotally attached to arm 114 of a lock bell crank indicated generally at 116. The lock bell crank 116 is pivotally mounted to the base 32 by a pin 118 and includes a locking arm 120 containing a notch 122. An upstanding flange 124 is integral with the locking arm 120. The primary slide 60 contains a notch 126 and further includes an upstanding boss 128 which is engaged by the locking arm 120 when the boss 128 is received within notch 122.

With particular reference to FIGS. 6 and 7, the base 32 is formed so that it further contains an angularly disposed recess 130, illustrated in FIG. 4 and in phantom in FIG. 6, including a bottom portion 132 having a longitudinal slot 134 and a laterally disposed aperture 136 receiving a depending portion 138 of a tub out of balance switch actuating arm 140. The arm 140 is pivotally mounted in the base 32 by virtue of a molded cylindrical portion 140a being received in a vertical slot 14012 at one end of the angularly disposed recess 130. The arm 140 includes a vertical cylindrical actuating boss 140a that projects into an end portion 75 of slot 74 in slide 60 so as to raise secondary slide 76 when arm 140 is pivoted on cylindrical portion 140a by the spin tub engaging arm 142. The sensing arm 142 is secured to the depending portion 138 of the out of balance sensing arm 140 and is positioned for engagement by the spin tub 144 during an out of balance condition as illustrated in FIG. 2 so as to raise the secondary slide and open switch 94, thereby terminating the spin cycle. From the preceding description, it is apparent that arm 142 senses tub out of balance conditions such as when the load of clothes collects on one side of the tube. The

tub will gyrate in an orbital path engaging the sensing arm 142 which rotates actuating arm 140 about the cylindrical portion 140a moving the boss 1400 upwardly into contact with secondary slide 76. The slide 76 is moved a sufficient amount to disengage slide tab 78 from switch arm 79 thereby opening the switch 94. The

opening of switch 94 deenergizes solenoid assembly 104 and spring 112 extends armature 110 disengaging locking arm 120 from notch 126 in slide 60. As the lid is opened, spring 70 then moves slide 60 to a retracted position, unlatching lid 14 by rotating latch 58 out of the open-ing path of keeper 20 as shown in FIG. 3.

A schematic diagram of the automatic control circuitry of a washing machine including provisions of the subject invention is shown in FIG. 5. An agitate switch 146 is connected in series with a source of 115 volts and is in circuit ahead of a line switch 148 which is normally located in the washing machine cycle timer. The circuit includes the usual water level control switch 150 and a multi-position water temperature selector switch assembly 152 including switches 152a, b and c in combination with a hot fill valve 154 and a cold fill valve 156 operable to provide a desired water temperature as illustrated. A cycle timer motor 158 is also connected in the circuit and controls timer contact switches 159 as shown. The usual spin and agitate speed selector switch arrangement 160 is included thereby regulating the speed of motor 162 in accor- I dance with the cycle selected on the washing machine control panel. Switch assembly 164 is included in the control circuit for reversing the direction of operation of motor 162. The assembly includes switches 166 'and 168 which actuate simultaneously to change the direction of rotation ofthe motor 162 which actuates the agitator-in one direction and the spin tub in the other direction in accordance with usual practice. The aforementioned switch 94of the lid interlock mechanism of the subject invention, actuated when the washing machine lid is closed, is in series with a spin control switch 170 so that the circuit to the motor 162 conditioning the washing machine for a spinning clothes water extraction cycle cannot be effected unless the lid 14 is closed. Closure of switch 94 energizes thesolenoid assembly 104 actuating the second switch 100 of the subject mechanism to a closed position by virtue of locking arm, 120 being rotated into the slot 126 of slide 60. Movement'of the locking arm 120 rotates upstanding flange 124 into engagement with the operating button 101 of the switch 100 closing the switch thereby completing the circuit for spin operation'when the cycle timer motor has progressed sufficiently to demand spinning of the clothes in tub 144 as has been previously described.

While I have shown anddescribed a specific embodiment of the present invention it will, of course, be understood that many modifications and alternative constructions may be made without departing from the true spirit and scope of my invention. I therefore intend by the appended claims to cover all such modifications and alternative constructions as fall within the true spiritand scope of this invention.

I claim:

'1. In a clothes washing machine of the type including a cabinet having a lid pivotally mounted thereon for movement between open and closed positions and havinga rotatable tub therein for washing clothes and spin extracting water therefrom, anelectrical control circuit, an automatic timer in said circuit advancing an operational cycle including washing and spinning the clothes, the improvement comprising; a keeper secured to said lid, means actuated into latching engagement with said keeper by closure of said lid, means slidably movable between a normally biased retracted position and an extended position, said last means being slidably extended by closure of said lid, a locking member being moved into engagement with said means in response to the extended movement thereof, movement of said locking member closing a switch in said control circuit conditioning the circuit for the water extracting cycle, and a switch actuator attached to said last means responding to out-of-balance conditions of said tub during the spin cycle opening the switch whereby said locking member disengages said last means thereby unlatching the lid for opening thereof and redistribution of the clothes in said tub.

2. In a clothes washing machine including a cabinet having a rotatable clothes washing tub therein, a lid pivotally mounted on said cabinet for movement between open and closed positions providing access to said tub, means in said cabinet agitating the clothes in said tub during a washing cycle and spinning said tub during a centrifugal water extraction cycle, an electrical control circuit including a timer automatically controlling the washing and spin cycles, a keeper secured to said cabinet lid, latch means secured to said cabinet and movable between a keeper engaged latched position and a disengaged unlatched position, means actuated by closure of said lid moving said latch means into the keeper engaged latched position, a slide member, said slide member also being moved from a normally biased retracted position to an extended position by said actuating means while said keeper is being latched, a locking member movable into and out of locking engagement with said slide in its extended position, a solenoid in said electrical control circuit, a first switch in said control circuit being closed by the extended movement of said slide energizing said solenoid, said locking member being moved into engagement with said slide locking it in its extended position, a second switch in said control circuit, said locking member closing said second switch when moved by said solenoid conditioning the water extraction circuit so that the tub spinning cycle can occur when demanded by the automatic timer, and a switch actuator attached to said slide responsive to out-of-balance conditions occurring during the spin water extraction cycle whereby sufficient orbital movement of said tub moves the actuator opening said first switch deenergizing said solenoid and unlocking said slide allowing unlatching the cabinet lid for rearranging the clothes in said tub.

3. In a clothes washing machine including a cabinet having a rotatable clothes washing tub therein, a lid pivotally mounted on said cabinet for movement between open and closed positions providing access to said tub, means in said cabinet agitating the clothes in said tub during a washing cycle and spinning said tub during a centrifugal water extraction cycle, an electrical control circuit including a timer automatically controlling the washing and spin cycles, a keeper secured to said cabinet lid, a latch and switch housing secured to said cabinet, a door latch pivotally mounted on said housing, said housing containing an axially extending slot, a primary slide movable in said housing slot between a normally biased retracted and extended positions, said primary slide containing an axially extending slot, a secondary switch actuating slide movable in said primary slide slot and carried therewith when said primary slide moves to its extended position, a bell crank lock pivotally mounted on said housing, a solenoid having an armature connected to one arm of said lock, a first switch attached to said housing in circuit with said solenoid, a second switch attached to said housing in circuit with the spin cycle portion of said control circuit, a latch and slide actuator mounted for slidable movement vertically in said housing, closure of said lid moving said latch and slide actuator vertically downwardly rotating said latch into a position blocking movement of said keeper open and simultaneously moving said primary slide to an extended position in said housing slot whereupon said secondary switch actuating slide closes said first switch energizing said solenoid, said solenoid rotating the other arm of said bell crank lock into engagement with said primary slide retaining it in the extended position, the rotating movement of said lock also closing said second switch in the spin circuit whereby the control timer is effective to spin the tub as prescribed during a washing cycle, and

a leaf spring switch actuator secured to said housing and positioned to respond to excessive out-of-balance conditions of said tub during a spin cycle, said leaf spring being movable by said tub to open said first switch deenergizing said solenoid unlocking said slide which retracts upon opening the cabinet lid.

4. The device as described in claim 3 wherein said door latch is in the form of a pivotally mounted bell crank one arm of which is engaged by said latch and slide actuator while the other am is rotated into a keeper locking position upon downward movement of said latch and slide actuator, said latch and slide actuator comprising a bifurcated member having respective sides thereof movable in guide slots in said housing, and said leaf spring switch actuator being pivotally mounted to said housing whereby engagement thereof by the tub during an out-of-balance condition pivots the leaf spring actuator raising said switch actuator second slide in said first slot upwardly to move the latter out of engagement with said first switch thereby opening the circuit to said solenoid and unlocking said first slide which retracts upon opening of said lid.

0' II II 

1. In a clothes washing machine of the type including a cabinet having a lid pivotally mounted thereon for movement between open and closed positions and having a rotatable tub therein for washing clothes and spin extracting water therefrom, an electrical control circuit, an automatic timer in said circuit advancing an operational cycle including washing and spinning the clothes, the improvement comprising; a keeper secured to said lid, means actuated into latching engagement with said keeper by closure of said lid, means slidably movable between a normally biased retracted position and an extended position, said last means being slidably extended by closure of said lid, a locking member being moved into engagement with said means in response to the extended movement thereof, movement of said locking member closing a switch in said control circuit conditioning the circuit for the water extracting cycle, and a switch actuator attached to said last means responding to out-of-balance conditions of said tub during the spin cycle opening the switch whereby said locking member disengages said last means thereby unlatching the lid for opening thereof and redistribution of the clothes in said tub.
 2. In a clothes washing machine including a cabinet having a rotatable clothes washing tub therein, a lid pivotally mOunted on said cabinet for movement between open and closed positions providing access to said tub, means in said cabinet agitating the clothes in said tub during a washing cycle and spinning said tub during a centrifugal water extraction cycle, an electrical control circuit including a timer automatically controlling the washing and spin cycles, a keeper secured to said cabinet lid, latch means secured to said cabinet and movable between a keeper engaged latched position and a disengaged unlatched position, means actuated by closure of said lid moving said latch means into the keeper engaged latched position, a slide member, said slide member also being moved from a normally biased retracted position to an extended position by said actuating means while said keeper is being latched, a locking member movable into and out of locking engagement with said slide in its extended position, a solenoid in said electrical control circuit, a first switch in said control circuit being closed by the extended movement of said slide energizing said solenoid, said locking member being moved into engagement with said slide locking it in its extended position, a second switch in said control circuit, said locking member closing said second switch when moved by said solenoid conditioning the water extraction circuit so that the tub spinning cycle can occur when demanded by the automatic timer, and a switch actuator attached to said slide responsive to out-of-balance conditions occurring during the spin water extraction cycle whereby sufficient orbital movement of said tub moves the actuator opening said first switch deenergizing said solenoid and unlocking said slide allowing unlatching the cabinet lid for rearranging the clothes in said tub.
 3. In a clothes washing machine including a cabinet having a rotatable clothes washing tub therein, a lid pivotally mounted on said cabinet for movement between open and closed positions providing access to said tub, means in said cabinet agitating the clothes in said tub during a washing cycle and spinning said tub during a centrifugal water extraction cycle, an electrical control circuit including a timer automatically controlling the washing and spin cycles, a keeper secured to said cabinet lid, a latch and switch housing secured to said cabinet, a door latch pivotally mounted on said housing, said housing containing an axially extending slot, a primary slide movable in said housing slot between a normally biased retracted and extended positions, said primary slide containing an axially extending slot, a secondary switch actuating slide movable in said primary slide slot and carried therewith when said primary slide moves to its extended position, a bell crank lock pivotally mounted on said housing, a solenoid having an armature connected to one arm of said lock, a first switch attached to said housing in circuit with said solenoid, a second switch attached to said housing in circuit with the spin cycle portion of said control circuit, a latch and slide actuator mounted for slidable movement vertically in said housing, closure of said lid moving said latch and slide actuator vertically downwardly rotating said latch into a position blocking movement of said keeper open and simultaneously moving said primary slide to an extended position in said housing slot whereupon said secondary switch actuating slide closes said first switch energizing said solenoid, said solenoid rotating the other arm of said bell crank lock into engagement with said primary slide retaining it in the extended position, the rotating movement of said lock also closing said second switch in the spin circuit whereby the control timer is effective to spin the tub as prescribed during a washing cycle, and a leaf spring switch actuator secured to said housing and positioned to respond to excessive out-of-balance conditions of said tub during a spin cycle, said leaf spring being movable by said tub to open said first switch deenergizing said solenoid unlocking said slide which retracTs upon opening the cabinet lid.
 4. The device as described in claim 3 wherein said door latch is in the form of a pivotally mounted bell crank one arm of which is engaged by said latch and slide actuator while the other arm is rotated into a keeper locking position upon downward movement of said latch and slide actuator, said latch and slide actuator comprising a bifurcated member having respective sides thereof movable in guide slots in said housing, and said leaf spring switch actuator being pivotally mounted to said housing whereby engagement thereof by the tub during an out-of-balance condition pivots the leaf spring actuator raising said switch actuator second slide in said first slot upwardly to move the latter out of engagement with said first switch thereby opening the circuit to said solenoid and unlocking said first slide which retracts upon opening of said lid. 